On 8 February your 0800 zone time position is LAT 21°55'S, LONG 52°27'W. Your vessel is on course 056°T at a speed of 17.5 knots. An observation of the Sun's lower limb is made at 0938 zone time, and the observed altitude (Ho) is 46°06.5'. The chronometer reads 12h 37m 23s, and the chronometer error is 1m 24s slow. LAN occurs at 1243 zone time, and a meridian altitude of the Sun's lower limb is made. The observed altitude (Ho) for this sight is 83°56.1'. Determine the vessel's 1200 zone time position.

Question

Accepted Answer

Option B: LAT 21°04.0'S, LONG 51°21.5'W. Advance the 0938 ZT sun line to the time of LAN using the vessel's course and speed. Calculate the latitude at LAN using the meridian altitude formula. Intersect the advanced line of position with the meridian latitude to determine the vessel's position at 1200 zone time.